The Night Shift Mode is said to be the highlight of the upcoming OS updateApple

Apple has rolled out the third iOS 9.3 beta for members of its public beta program, two days after it was released for developers. Verizon subscribers in the US, who registered for the beta tests, will now have access to the WiFi calling feature once the build is updated on iPhones and iPads.

The US-network provider's move comes a little late as T-Mobile, AT&T and Sprint are already offering the WiFi calling feature in the country. The third beta of Apple iOS 9.3 includes a carrier update for T-Mobile users that fixes a bug preventing apps from loading on a cellular connection.

Other major enhancements include an improved method for locking and unlocking items in Notes and minor tweaks in Night Shift option bar in Control Center along with fixed icons in landscape.

The iOS 9.3 was rolled out at the start of the year with a number of new features including sleep-enhancing Night Shift mode, CarPlay and Health app related features. iPhone 6s and 6s Plus users additionally have access to 3D Touch short-cuts introduced in the last beta test done by Apple a few weeks back.

Moreover, news apps in iOS 9.3 can be further personalised to suit a user's interests. The new OS will focus on education-based features like Shared iPad for students, a Classroom app, Apple School Manager and Managed Apple IDs.

The worldwide release date of the iOS 9.3 has not been officially announced, but going by the constant beta tests, it seems the company may release the OS in time for Apple's March event.